EP0144918B1 - Verfahren zur Verbrennung von fliessfähigen Brennstoffen - Google Patents

Verfahren zur Verbrennung von fliessfähigen Brennstoffen Download PDF

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Publication number
EP0144918B1
EP0144918B1 EP84114482A EP84114482A EP0144918B1 EP 0144918 B1 EP0144918 B1 EP 0144918B1 EP 84114482 A EP84114482 A EP 84114482A EP 84114482 A EP84114482 A EP 84114482A EP 0144918 B1 EP0144918 B1 EP 0144918B1
Authority
EP
European Patent Office
Prior art keywords
resonator
diffuser
sound
sound generator
combustion
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP84114482A
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English (en)
French (fr)
Other versions
EP0144918A3 (en
EP0144918A2 (de
Inventor
Mats Olsson
Roland Sandström
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
INSAKO AB
Original Assignee
INSAKO AB
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by INSAKO AB filed Critical INSAKO AB
Priority to AT84114482T priority Critical patent/ATE45211T1/de
Publication of EP0144918A2 publication Critical patent/EP0144918A2/de
Publication of EP0144918A3 publication Critical patent/EP0144918A3/en
Application granted granted Critical
Publication of EP0144918B1 publication Critical patent/EP0144918B1/de
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D11/00—Burners using a direct spraying action of liquid droplets or vaporised liquid into the combustion space
    • F23D11/34—Burners using a direct spraying action of liquid droplets or vaporised liquid into the combustion space by ultrasonic means or other kinds of vibrations
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C99/00—Subject-matter not provided for in other groups of this subclass
    • F23C99/003—Combustion process using sound or vibrations
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23C—METHODS OR APPARATUS FOR COMBUSTION USING FLUID FUEL OR SOLID FUEL SUSPENDED IN  A CARRIER GAS OR AIR 
    • F23C15/00—Apparatus in which combustion takes place in pulses influenced by acoustic resonance in a gas mass
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F23—COMBUSTION APPARATUS; COMBUSTION PROCESSES
    • F23D—BURNERS
    • F23D1/00—Burners for combustion of pulverulent fuel

Definitions

  • the invention relates to a method for the combustion of fluidal fuels according to the prior art portion of claim 1 as well as an apparatus for carrying out the method.
  • fluidal fuels covers liquid, gaseous and atomized (pulverized) fuels.
  • Volatile components of the fuel are combusted in the precombustion chamber, and the flame is directed into a flame tube.
  • the pulsations of the flame in the precombustion chamber are propagated into the flame tube wherein the column of gas is set in resonance so as to move relatively with respect to the fuel particles, which speeds up the combustion as mentioned above.
  • SE-B-7701764-8 (publication No. 412 635) describes a method of combusting atomized solid, liquid or gaseous fuels, which is based on the principle mentioned by Reynst.
  • the vibrations are not generated by the burner flame.
  • Sound energy is supplied to the combustion flame by external means such as a sound emitter, the frequency of the sound ranging from infrasonic to ultrasonic frequencies.
  • the method described in the SE-B-7701764-8 apparently has not yet been utilized in practice to any significant extent, which may indicate that it has not been possible so far to develop the method for industrial application.
  • the USSR Author's Certificate 228216 (V. S. Severyanin) describes a pulsating combustion in a bed whereby the hot grid of the Rijke tube is replaced by a layer of solid fuel in which free oscillation will develop. The effect obtained is, however, relatively low, because only self- generated oscillation is utilized.
  • US-A-2 945 459 discloses a pulsating combustion method and an apparatus wherein pulsating air is supplied to a combustion chamber forming part of a resonance tube receiving the pulsating air.
  • the resonance frequency of the tube is adjusted by means of a plunger closing one end of the tube, the other end being open.
  • the fuel to be combusted is supplied to the air in the resonance tube between the ends thereof.
  • a carburetor system for a motor car engine in which the combustion air is supplied to the carburetor via a long rectilinear tube at the end of which which faces away from the carburetor a sound source is attached that induces an oscillation of the air column in said rectilinear supply tube.
  • the length of the tube is adjusted to the frequency of the sound source.
  • the fuel is supplied to the resonator, where the particle velocity is at maximum therein.
  • the invention aims at a method of the above- mentioned kind which further improves the beneficial effect of sound on combustion and which can be industrially applied in a practical manner.
  • the invention aims also at an apparatus for carrying out the method.
  • An apparatus for carrying out the method according to the invention is characterized by the features of claim 7.
  • the maximum velocity of the reciprocating air in the resonator the so-called particle velocity
  • the fuel particles are oscillated by the reciprocating air column produced by the sound generator such that the fuel particles will be more intimately entrained into the air thereby increasing the combustion rate.
  • the flame will be shorter than without the application of sound activation.
  • the frequency of the air pulses fed into the resonance tube is not defined and in any case is not defined as the fundamental natural frequency of the resonance tube.
  • the position where the fuel is supplied to the resonance tube is defined as the position where the particle velocity is at maximum.
  • the burner shown in the Figures 1 to 3 comprises a tubular resonator 10, having a length of a quarter of the wave length of the sound emitted.
  • a feeder 11 termed exigator for the purpose of this specification, is arranged at one end of the resonator, thus forming together with the resonator 10 a low frequency sound generator.
  • the exigator is connected to a supply conduit 12 for driving gas.
  • the generator can be an infrasound generator of the positive feedback type described in US-A-4359 962. However, any other infrasound generator can be used for the purpose of the invention.
  • the resonator 10 forms a 90° bow 13 and terminates in a diffuser 14, the bow and the diffuser forming part of the quarter wave resonator.
  • the diffusor is surrounded by an air jacket 15 provided with a tangential inlet 16 for pressurized combustion air.
  • the burner is mounted to the outside of a boiler wall 18, the outlet of the diffuser 14 being substantially flush with the inside surface of the wall 18.
  • the jacket 15 forms an annular outlet opening, vanes 19 ( Figure 3) being provided in the annular opening to form spacers between the jacket and the diffuser. As shown in Figure 3 these vanes 19 are angled to the axial direction of the diffuser in order to impart a rotational movement about the axis of the diffuser to the combustion air discharged through the annular outlet opening of the air jacket 15.
  • a guide tube 20 extends through the bow 13 along the axis of the diffuser 14 and is mounted in the bow by means of arms 21.
  • a lance 22 for the supply of fluidal fuels is displaceably received by the guide tube 20 to be adjusted in the axial direction thereof.
  • the lance 22 is arranged for the supply of pulverized coal, and is provided at its outlet end, which opens in the diffuser, with a conical body 23, which is mounted in the lance 22 by means of arms 24 with the apex of the conical body facing the interior of the lance.
  • an annular flange 25 is provided such that pulverized coal supplied through the lance by pressurized air and entrained therein will be diverted by the conical body 23 and said flange 25 substantially in the radial direction towards the periphery of the diffuser 14.
  • the lance 22 can be adjusted axially so as to supply the fuel at an optimal location in the diffuser.
  • the outlet end of the lance 22 can be arranged in other ways than the one disclosed herein for the supply of fluidal fuels of other types such as pulverized peat, wood dust, coal-water slurry, or other slurries containing coal, or other slurries, oil, or gas.
  • fluidal fuels of other types such as pulverized peat, wood dust, coal-water slurry, or other slurries containing coal, or other slurries, oil, or gas.
  • pulverized coal this is supplied by means of pressurized air to be dispersed in the air.
  • the air thus supplied together with the fuel is supplemented by the air supply through the resonator 10 for operating the exigator 11, and further combustion air is supplied through the inlet 16 via the air jacket 15 to be discharged through the annular outlet opening thereof.
  • the resonator 10 of the low frequency sound generator is of the quarter wave length type and is operated at its fundamental (first harmonic) tone, having a frequency of a maximum of 60 Hz.
  • the maximum frequency should be 30 Hz; however, 20 Hz or less would be optimal.
  • Lance 22 is adjusted such that the supply of the fuel takes place at an optimal position in the diffuser 15. The particles of the fluid supplied as well as the air and other gases in the area at the opening of the resonator accordingly are given a reciprocating movement under the influence of the sound, whereby the combustion of the fuel is intensified.
  • the isotherms are shown for burning oil without activation by means of low frequency sound
  • the isotherms are shown for burning oil with low frequency sound activation according to the invention.
  • the length of the flame is substantially shorter with sound activation than without sound activation. It has also been found that the flame is partly drawn into the resonator when this is terminated by a diffuser, which also contributes to shortening of the flame.
  • the temperature at the base of the flame will be increased by sound activation, but due to the fact that the diffuser is cooled by combustion air supplied through the jacket, the diffuser can stand this higher temperature without being made of an expensive heat resistant material.
  • the frequency of the low frequency sound generator should be chosen such that the length of the flame is less than a quarter of the wave length of the sound.

Landscapes

  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluidized-Bed Combustion And Resonant Combustion (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Treatment Of Water By Ion Exchange (AREA)
  • Medicines Containing Antibodies Or Antigens For Use As Internal Diagnostic Agents (AREA)
  • Centrifugal Separators (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Chairs Characterized By Structure (AREA)
  • Feeding And Controlling Fuel (AREA)
  • Devices And Processes Conducted In The Presence Of Fluids And Solid Particles (AREA)

Claims (8)

1. Verfahren zur Verbrennung von strömungsfähigen Brennstoffen, wobei sich der Brennstoff in zerstäubtem Zustand in Verbennungsluft befindet und der Wirkung eines Schalles ausgesetzt ist, der von einem Schallgenerator erzeugt wird, zu welchem ein rohrförmiger Resonator mit einem geschlossenen und einem offenen Ende gehört, und wobei Verbrennungsluft durch den rohrförmigen Resonator zugeführt wird, während der Brennstoff durch ein Zuführrohr (22) zugeführt wird, welches in den rohrförmigen Resonator mündet, bei welchem Verfahren der Schallgenerator mit der Grundfrequenz des Resonators betrieben wird, die höchstens 60 Hz beträgt, und das Mischen von Brennstoff und Verbrennungsluft in einem als Diffuser geformten Teil am offenen Ende des Resonators stattfindet, wo die Partikelgeschwindigkeit, die von dem vom Resonator erzeugten Schall verursacht wird, im wesentlichen ein Maximum hat.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, daß nur ein Teil der Verbennungsluft durch den Resonator des Schallgenerators geführt wird.
3. Verfahren nach Anspruch 2, dadurch gekennzeichnet, daß ein weiterer Teil der Verbrennungsluft in Gestalt eines kreisförmigen Vorhanges über den Umfang des offenen Endes des Resonators zugeführt wird.
4. Verfahren nach Anspruch 3, dadurch gekennzeichnet, daß die ein genannten Vorhang bildende Verbrennungsluft um die Achse des offenen Endes des Resonators rotiert wird.
5. Verfahren nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Frequenz des niederfrequenten Sqhallgenerators so gewählt wird, daß die Länge der Flamme kleiner ist als ein Viertel der Wellenlänge des Schalls.
6. Verfahren nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß der Schallgenerator mit einer positiven Rückkopplung arbeitet.
7. Vorrichtung zur Durchführung des Verfahrens gemäß einem der vorhergehenden Ansprüche mit einem Schallgenerator (t 0,11), zu dem ein rohrförmiger Resonator (10) mit einem geschlossenen und einem offenen Ende gehört, mit einem Zuführrohr (12) für Verbrennungsluft, die durch den rohrförmigen Resonator strömt, und mit einem Zuführrohr (22) für strömungsfähigen Brennstoff, welches Zuführrohr in den rohrförmigen Resonator mündet, dadurch gekennzeichnet, daß der Resonator des Schallgenerators (10, 11) eine Länge von einem Viertel der Wellenlänge des vom Generator abgegebenen Schalles hat und eine Eigengrundfrequenz von maximal 60 Hz hat, daß das Resonatorrohr einen rohrförmigen Abschnitt und einen Diffuser (14) am offenen Ende des Resonators hat, wobei der Diffuser die Austrittsöffnung bildet, daß das Zuführrohr (22) für die Zufuhr von strömungsfähigem Brennstoff im Inneren des genannten Diffusers mündet und längs der Achse des Diffusers verstellbar ist und daß der Diffuser von einem für Luft bestimmten Mantel umgeben ist, welcher eine das Austrittsende des Diffusers umgebende ringförmige Austrittsöffnung bildet.
8. Vorrichtung nach Anspruch 7, dadurch gekennzeichnet, daß in der ringförmigen Austrittsöffnung Leitschaufeln (19) angeordnet sind, die gegenüber der Achse des Diffusors (14) abgewinkelt sind.
EP84114482A 1983-12-02 1984-11-29 Verfahren zur Verbrennung von fliessfähigen Brennstoffen Expired EP0144918B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT84114482T ATE45211T1 (de) 1983-12-02 1984-11-29 Verfahren zur verbrennung von fliessfaehigen brennstoffen.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE8306653 1983-12-02
SE8306653A SE458799B (sv) 1983-12-02 1983-12-02 Saett och anordning foer foerbraenning av fluida braenslen

Publications (3)

Publication Number Publication Date
EP0144918A2 EP0144918A2 (de) 1985-06-19
EP0144918A3 EP0144918A3 (en) 1986-08-13
EP0144918B1 true EP0144918B1 (de) 1989-08-02

Family

ID=20353553

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84114482A Expired EP0144918B1 (de) 1983-12-02 1984-11-29 Verfahren zur Verbrennung von fliessfähigen Brennstoffen

Country Status (16)

Country Link
US (1) US4650413A (de)
EP (1) EP0144918B1 (de)
JP (1) JPS60211214A (de)
KR (1) KR850004312A (de)
AT (1) ATE45211T1 (de)
AU (1) AU569561B2 (de)
BR (1) BR8406111A (de)
CA (1) CA1237650A (de)
DE (1) DE3479234D1 (de)
DK (1) DK564584A (de)
ES (1) ES8606610A1 (de)
FI (1) FI84394C (de)
IN (1) IN162295B (de)
SE (1) SE458799B (de)
SU (1) SU1452494A3 (de)
ZA (1) ZA849348B (de)

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SE8500276D0 (sv) * 1985-01-22 1985-01-22 Asea Stal Ab Method of mixing fluids and apparatus for working the method
DE3523436A1 (de) * 1985-06-29 1987-01-08 Steag Ag Verfahren zur verbrennung von kohlenstaub unter zufuehrung von luft mit einem kohlenstaubbrenner
GB8626562D0 (en) * 1986-11-06 1986-12-10 Wells A A Gas resonance device
SE463785B (sv) * 1988-11-01 1991-01-21 Infrasonik Ab Foerfarande och anordning foer att med hjaelp av laagfrekvent ljud forcera vaermetransmission mellan kroppar och gaser
SE465731B (sv) * 1990-02-07 1991-10-21 Kamyr Ab Utvinning av energi och kemikalier ur massaavlutar under exponering av laagfrekvent ljud
SE468772B (sv) * 1991-05-30 1993-03-15 Goetaverken Energy Ab Utvinning av energi och kemikalier ur avlut i en sodapanna under exponering av laagfrekvent ljud
WO1994014003A1 (en) * 1992-12-15 1994-06-23 Bha Group, Inc. Acoustically enhanced combustion method and apparatus
US5785012A (en) * 1992-12-15 1998-07-28 Bha Group Holdings, Inc. Acoustically enhanced combustion method and apparatus
US5461123A (en) * 1994-07-14 1995-10-24 Union Carbide Chemicals & Plastics Technology Corporation Gas phase fluidized bed polyolefin polymerization process using sound waves
JP5485193B2 (ja) 2011-01-26 2014-05-07 大陽日酸株式会社 バーナの燃焼方法
SE540254C2 (en) 2016-10-31 2018-05-15 Olsson Mats An infrasound generator for enhancing the combustion of solid fuels
CN114543984B (zh) * 2022-04-22 2022-07-05 北京航空航天大学 一种Rijke管边界耗散的定量调节装置及方法

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DE1031461B (de) * 1954-07-30 1958-06-04 Walther & Cie Ag Anordnung zur Waermeuebertragung in einer Brennkammer, die mit einer Feuerung mit schwingender Verbrennung betrieben wird
US3690807A (en) * 1970-11-16 1972-09-12 Paxve Inc Burner
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SU567015A1 (ru) * 1975-03-07 1977-07-30 Предприятие П/Я А-1687 Камера пульсирующего горени
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Title
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Also Published As

Publication number Publication date
SU1452494A3 (ru) 1989-01-15
IN162295B (de) 1988-04-23
FI84394B (fi) 1991-08-15
BR8406111A (pt) 1985-09-24
US4650413A (en) 1987-03-17
DK564584D0 (da) 1984-11-28
SE458799B (sv) 1989-05-08
EP0144918A3 (en) 1986-08-13
FI844739L (fi) 1985-06-03
EP0144918A2 (de) 1985-06-19
AU3607684A (en) 1985-06-06
CA1237650A (en) 1988-06-07
SE8306653L (sv) 1985-06-03
ES8606610A1 (es) 1986-04-01
DK564584A (da) 1985-06-03
ZA849348B (en) 1986-09-24
FI84394C (fi) 1991-11-25
SE8306653D0 (sv) 1983-12-02
ES538187A0 (es) 1986-04-01
AU569561B2 (en) 1988-02-04
JPS60211214A (ja) 1985-10-23
FI844739A0 (fi) 1984-11-30
KR850004312A (ko) 1985-07-11
ATE45211T1 (de) 1989-08-15
DE3479234D1 (en) 1989-09-07

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